Contributions to https://mwvsciencefair.wikispaces.com/ are licensed under a Creative Commons Attribution 3.0 License. 
Portions not contributed by visitors are Copyright 2018 Tangient LLC
TES: The largest network of teachers in the world
Portions not contributed by visitors are Copyright 2018 Tangient LLC
TES: The largest network of teachers in the world
Loading...
Table of Contents
Title: Wind Tunnel
Specific Question:
What shapes are more aerodynamic?Hypothesis:
I hypothesize that the wing will be the most aerodynamic because it offers the least resistance to the wind and that the block will be the least aerodynamic because it is more blunt.Graph of Hypothesis:
Variables:
Independent Variable: Different shaped blocks
Dependent Variable: Distance shape travels in wind
Variables That Need To Be Controlled: Tunnel path must be consistent for each object
Vocabulary List That Needs Explanation:
Aerodynamics: "The branch of mechanics that deals with the motion of air and other gases and with the effects of such motion on bodies in the medium." - Dictionary.comWind Tunnel: "A tubular chamber or structure in which a steady current of air can be maintained at a controlled velocity, equipped with devices for measuring and recording forces and moments on scale models of complete aircraft or of their parts or, sometimes, on full-scale aircraft or their parts." -
Dictionary.com
Drag Coefficient: "The ratio of the drag on a body moving through air to the productof the velocity and surface area of the body." - Dictionary.com
General Plan:
An experiment was conducted to determine which shape was more aerodynamic. In this experiment, a wind tunnel was constructed to find out which of four shapes, a cube, a sphere, a wedge, and an airplane wing, had the less aerodynamic drag.A wire was used as a frame and shrink wrap covered the wind tunnel then a string was used to harness the test object. The test shapes were made out of balsa wood.The test shapes were the following shapes: Cube, Sphere, Wedge, Wing. The test shapes were hung from a string which was fastened to the roof of the wind tunnel. A ruler was put on the side of the wind tunnel and a high speed camera was used to video tape the results. The goal of this experiment was that the more drag the object had the farther back it will be pushed by the air current which was measured by the ruler. This was done at school however work was conducted towards making the wind tunnel at home.
...
Safety Or Environmental Concerns:
Half way through the experiment, the metal safety screen came off the fan. Tape was put over it in an "X" like fashion to prevent people from tampering with it.Experimental Design:
(add the correct headings from the experimental design page before beginning)Resources and Budget Table:
Data Table:
Time Line:
3/2/12complete design and collection of all materials3/8/12run a test of the set up, not collection data, just seeing if everything works
3/20/12complete all trails of experiment and all data collection
3/30/12complete all data analysis, mean, median, range, graphs
4/9/12complete results and conclusions write up.
Background Research:
The wedge's drag coefficients was 1.14. The wing's drag coefficients was 0.045. The sphere's drag coefficients was 0.07. The block's drag coefficients was 1.05.References:
http://exploration.grc.nasa.gov/education/rocket/shaped.htmlDetailed Procedure:
A shape will be put in the wind tunnel and attached to a string. Then an industrial fan will be turned on that will push air through the tunnel. When an object has drag it will swing backwards. The farther back it will go, which will be measured by a ruler on the side of the wind tunnel wall and recorded by a high-speed camera, will determine the drag of the object.Photo List:
Results:
An experiment was conducted to find out what shape was more aerodynamic. Tests were conducted on a sphere, a block, a wedge, and a wing. The most aerodynamic shape was the sphere. The least aerodynamic was the block. The sphere’s results were as follows: 65.2, 66.5, 67.6, and 65.3. The block’s results were as follows: 26, 39.4, 34.9, and 34.8. The wedge’s results were as follows: 65.9, 64, 65.3 and 67.7. The wing’s results were as follows: 65, 34.9, 62, and 62.7. The mean for the sphere was 66.15, the block: 33.78, the wedge: 65.73, the wing: 56.15.
All Raw Data:
Graphs:
Photos:
Data Analysis:
Conclusion:
This experiment was conducted to find out what shape was more aerodynamic. Tests were conducted on a sphere, a block, a wedge, and a wing. The mean distance the sphere traveled was 66.15 cm. The mean distance the block traveled was 33.78 cm. The mean distance the wedge traveled was 65b.73cm. The mean distance the wing traveled was 56.15 cm. It was determined that although the wedge seemed to travel the farthest and in a consistently straight line, the sphere was more consistent and its mean was the greatest. The sphere was the best because it had rounded edges which didn't give any more drag on one side than the other, so it would roll and not tumble.Discussion:
The overall outlook on the experiment a few days ago at first looked failed, however, once the time was put in and some of the problems it had were looked into more thoroughly, it was working well in no time. First the entire idea for the shapes to be attached to the wind tunnel had to be done. Instead of having several rubber bands attached to it almost like a harness, which restricted it from going anywhere, instead, a small string was tied to the top of the tunnel right in front of the fan and to the middle of the shape. It was then set on an elongated runway and allowed it to slide freely, thus showing how well the objects sliced through the air. For example, on one of the trials the most aerodynamic shape, the wedge, went completely straight down the runway until the air current was no longer strong enough to carry it any further, and the least aerodynamic shape, the block, didn't even make it halfway down the runway before toppling and tumbling. Now one could feel confident in saying that this project was a success in explaining in somewhat depth about each shape and how aerodynamic it is.
The question was to see which shape was the most aerodynamic of the group of four shapes, the information that was extracted from this experiment was brought about by the use of a wind tunnel, this wind tunnel was constructed through the use of a fan and several pieces of wire and sheets of plastic.
In the hypothesis, it was predicted that the wing would do the best, the second best would be the wedge then the sphere and then the block. In the actual experiment, however, the wedge did the best the wing and the sphere were about tied and the block did the worst. It was believed that this happened because the wing was meant to be suspended in mid air for it to work to the full of its potential, but in the experiment, all the experiments were on the ground, which made it perfect conditions for the wedge which was flat on the bottom, good for sliding, and was tall in the back and short in the front, which made it easy to get pushed from the back by the air and slide through the air with the pointy front. It was believed that the wing was designed more for lift than aerodynamics.
It was found interesting to note that the wing, which is used most by airplanes and was designed by scientists, was the most unpredictable, sometimes going fast and sometimes toppling as if it were a block. It was believed that this was because it was meant to achieve lift and not to go straight, because of this and that it was on the ground, the edges were too abrupt and caused toppling.
During the planning stage of the experiment, it sounded easy enough, but once the experiment was actually tried, it was found to have many problems. After looking into these problems, it was realized that the way the shape was attached to the wind tunnel had to be redone. After that the airflow had to be fortified; made sure that no air was escaping and making an alternate current of air flow. To do this, it was needed to completely tape the wind tunnel down, isolating any air pockets and make sure that there was an extended runway.
In doing this experiment, there were certain components that needed to be procured first. These components were an industrial fan, heavy duty plastic sheets, duct tape, coat hanger wire, balsa wood, wood sticks, and a spool of string. In going into this experiment, there also needed to be previous knowledge on the subject. There needed to be research on the different shapes, how to carve them accurately and how to make it so that they all had the same mass.
Benefit to Community and/or Science:
The knowledge gained from this experiment can help car companies develop cars that are more gas efficient and that are more wind resistant. This can also help consumers in our community know which cars would be best for them, gas efficiency wise, and environmentally wise.Abstract:
A Wind tunnel was constructed consisting of a sheet of plastic over a wire frame. An industrial fan was used to provide the wind current for the experiment. A fan was placed at one end of the wind tunnel and the other was left open. This experiment was conducted to find out what shape was more aerodynamic. Tests were conducted on a sphere, a block, a wedge, and a wing. The mean distance the sphere traveled was 66.15 cm. The mean distance the block traveled was 33.78 cm. The mean distance the wedge traveled was 65b.73cm. The mean distance the wing traveled was 56.15 cm. It was determined that although the wedge seemed to travel the farthest and in a consistently straight line, the sphere was more consistent and its mean was the greatest. The sphere was the best because it had rounded edges which didn't give any more drag on one side than the other, so it would roll and not tumble.